Semiconductor, solar cells, or other types of substrates may be processed within various substrate processing systems, such as ion implantation systems, deposition systems and etching systems. Some ion implantation systems may comprise an ion source, extraction electrodes, a mass analyzer, a collimating magnet, one or more acceleration or deceleration stages and a process chamber that holds the substrate. Deposition systems may comprise an ion source, and a target and substrate disposed in a process chamber. It is common for components disposed within these systems, such as the interior walls, electrodes, insulators and other equipment to show signs of deterioration or to become coated. This may be due to two different causes. For example, ions or other materials may be deposited on these components. In addition, the components themselves may create particulates when struck by energetic ions, causing contamination downstream. For example, the inner walls of the mass analyzer may be impinged by energetic ions, causing the material used to construct the mass analyzer to sputter. Additionally, materials released further upstream, such as within the ion source, may be deposited on and coat the walls of the mass analyzer. After a layer of sufficient thickness forms, this coating may flake off, causing contamination downstream. In other embodiments, in regions near the substrate, a thin film of photoresist may form on these components.
Currently, liners typically made from graphite are used to address these issues. Graphite is carbon based. Therefore, even if the liner is subject to sputtering, the release of carbon may have a minimal impact to components and substrates disposed downstream. In addition, graphite can be mechanically textured to form a rough inner surface. The textured graphite may have features that are about 0.3 mm in depth. The deposited materials that coat the liner adhere well to this textured surface, thereby reducing the likelihood of flaking.
However, one disadvantage of graphite is that it tends to particulate when struck by energetic ions. This may be due to the microstructure of graphite, which is an assembly of small carbon grains held together in an amorphous carbon matrix. Therefore, it would be advantageous if there were a liner and a texturing method while could be used in ion implantation systems that resisted particulating and did not allow flaking of deposited coatings.